At most places I worked (manufacturing), we tested our products in their shipping containers by dropping them from about four feet onto asphalt, to simulate a drop from a truck or a dock. We also shipped products to the east and west coasts, and had them returned to us for inspection.
There was one test that was rather demanding - hospital beds - and our products were the motors and controls that raised and lowered portions of the bed. Our customer, the bed manufacturer, would test the beds (with motors, controls, etc.) by pushing them down a flight of steps. Evidently, such a fall was not uncommon when beds were being moved around from one floor to the next. This was not a test of packaging, but a test of how much mishandling could a product endure.
For about three years, 20 years ago, I manufactured read-to-fly radio control giant-scale airplanes. These could have up to a 10-ft wingspan and weigh 50 lb. While most were either picked up or delivered in person, I shipped a number of them. The crates ranged from 4' x 3' x 6' to 4' x 4' x 8'. For transporting and shipping, the wings were removable, and sometimes the horizontal stab was also removable. Only once was there minor damage done to a 1" square aluminum spar. According to my customer, the crate was dropped during unloading from the delivery truck, landed on a corner (of course). and although there was some external damage to the crate, the airplane sustained minimal, easily repairable damage. Evidently, the crate slipped off the dolly used to slide it down the ramp when it was at the top of the ramp.
This was a test that I would have preferred had not happened, but when it did happen it gave me reassurance of my packaging.
Alex